Hi gerbils. I've been thinking about why Bulldozer-based processors won't work in older sockets for Stars cores-based Phenom II and Opteron products. It's a known fact that FX chips won't run on your AM3 boards, and many FM1 adopters were sent home disappointed when they found out Trinity chips won't work on FM1 boards. I read somewhere that the power delivery requirements of BD are so different from Stars to the point of not allowing BD to work with boards for those CPUs (Stars). But whatever the reason, I've realized that this is not applicable to servers. There, AMD was able to make 6200-series Opterons (BD based) work in older systems that supported Stars. Is it because AMD's partners were told how to include forward compatibility in those systems for BD-based CPUs? Which begs the question: why didn't AMD do the same thing with desktop platforms as well? Those Opteron 61xx systems probably shipped during the same time frame as FM1 boards, so AMD probably knew well enough that FM1 owners will want forward compatibility (not to mention AM3 owners), and if you say it may have had something to do with cost, consider this: AM3+ board support for BD and Stars doesn't really make it expensive. Any thoughts? If BD supported AM3, I would've sprung for it already.

If people stick with you just because you have a Rolex on your wrist, you can bet losing them is as OK as losing an Invicta. And if they stick with you even if you only have an Invicta, losing them is as OK as losing a Rolex.

As I understand it, AM3+ improves power management, tightens up the power regulation specs, and increases the maximum amount of power that can be delivered to the socket. AMD felt that these changes were necessary to properly support BD. I believe it is somewhat like the AM2/AM2+/AM3 situation, where some existing motherboards could support the newer CPUs with just a BIOS flash, but this is not officially supported by AMD.

I have no idea what the differences between FM1 and FM2 are.

On the server side, the power regulation specs were probably pretty tight to begin with.

The years just pass like trains. I wave, but they don't slow down.-- Steven Wilson

I know my motherboard is classified as AM3 but got bios updates for the CPU codes to allow it to use all of the FX chips. I have no idea if there is actually a limitation to certain AM3 boards or if it's artificial and up to the board makers to keep their older AM3 boards up to date for these processors.

I would check your board makers website and see if they have any bios updates available like mine did.

ronch wrote:Hi gerbils. I've been thinking about why Bulldozer-based processors won't work in older sockets for Stars cores-based Phenom II and Opteron products. It's a known fact that FX chips won't run on your AM3 boards, and many FM1 adopters were sent home disappointed when they found out Trinity chips won't work on FM1 boards. I read somewhere that the power delivery requirements of BD are so different from Stars to the point of not allowing BD to work with boards for those CPUs (Stars). But whatever the reason, I've realized that this is not applicable to servers. There, AMD was able to make 6200-series Opterons (BD based) work in older systems that supported Stars. Is it because AMD's partners were told how to include forward compatibility in those systems for BD-based CPUs? Which begs the question: why didn't AMD do the same thing with desktop platforms as well? Those Opteron 61xx systems probably shipped during the same time frame as FM1 boards, so AMD probably knew well enough that FM1 owners will want forward compatibility (not to mention AM3 owners), and if you say it may have had something to do with cost, consider this: AM3+ board support for BD and Stars doesn't really make it expensive. Any thoughts? If BD supported AM3, I would've sprung for it already.

JBI : Well, AMD could have used whatever allowed the old servers to support the new BD chips to make FM1 be forward-compatible with Trinity and avoid pissing off a lot of customers. I don't think it would have cost a lot.

If people stick with you just because you have a Rolex on your wrist, you can bet losing them is as OK as losing an Invicta. And if they stick with you even if you only have an Invicta, losing them is as OK as losing a Rolex.

(Besides what has already been mentioned regarding some AM3 mobos support FX chips with a BIOS flash, and that AM3+ offers power delivery improvements)

Intel does a socket refresh (almost) every time they introduce a new processor family. Whis is it such a big deal when AMD does the same. I can see this as both good and bad:

Good) New sockets show that (hopefully) significant architectural changes and/or feature additions have taken place to the CPU, Chipset, or both. I feel like you can only progress so far by keeping with the same socket. I think Intel updates sockets too often and AMD could use more frequent socket refreshes sometimes. But I don't think either company should be required to stick to a given number of CPU generations on a particular socket. If something needs to be changed it should.

Bad) As touched on in the good, we consumers are then stuck with the burden of having to buy a new motherboard along with that new processor. Nobody likes that. That's also why I tend to spend less on motherboards for my Intel systems. I don't mind paying a bit more for some luxuries on an AMD board that may get me through a processor upgrade 2 generations later. That being said, a lot can change in 3 years. (loop back to "good" section)

FM1 was designed to accomodate the IGP in Llano processors. It was never meant to house FX CPUs. The faint rumors for FM1 compatability with Trinity were only floating around shortly after the Llano launch. But I don't recall there ever being an official guarantee. AFAIK, it's been known for quite some time that Trinity would not be compatible with FM1. That being said, FM2 is said to be compatible with Richland APUs next year and maybe even one more beyond that. AM3+ supports Bulldozer, Piledriver, and purportedly Steamroller FX CPUs as well.

Yeats : Yes, I do understand that *some* AM3 motherboards do support FX, but the fact that most AM3 boards don't, means FX is not officially supported on AM3. It's strange. It's like AMD got sloppy on the socket. I know this is old news, but the question arises in light of Trinity's launch, and with folks who bought FM1 boards now more than ever feel being left out in the cold.

If people stick with you just because you have a Rolex on your wrist, you can bet losing them is as OK as losing an Invicta. And if they stick with you even if you only have an Invicta, losing them is as OK as losing a Rolex.

ronch wrote:Yeats : Yes, I do understand that *some* AM3 motherboards do support FX, but the fact that most AM3 boards don't, means FX is not officially supported on AM3. It's strange. It's like AMD got sloppy on the socket. I know this is old news, but the question arises in light of Trinity's launch, and with folks who bought FM1 boards now more than ever feel being left out in the cold.

As I understand it its not up to AMD to make that happen. Its up to the board makers to create the necessary BIOS update to allow that compatibility. That some boards have it and some boards don't makes that clear. The problem is that some manufacturers figure its better for the bottom line to force you to upgrade than make your current hardware compatible.

I am sometimes surprised at how long some sockets have lasted. Anymore I've come to expect that the initial mobo and CPU will ride into the sunset together, and that with a new CPU comes a new mobo. I think that many have come to expect if not demand that their mobo last through a couple or a few generations of CPU and are disappointed when it doesn't happen. I have come to consider it a bonus rather than an expectation, and am not disappointed when it does not happen.

Yup, I'm pretty much the same way. I was pleased when I discovered my old mATX AM2+ mobo had a BIOS update which would allow it to take a 1090T, but I would not have been particularly upset if it didn't. Tech marches on, and an AM3 mobo was needed to take full advantage of the 1090T anyhow (for DDR3 support).

The years just pass like trains. I wave, but they don't slow down.-- Steven Wilson

ronch wrote:Yeats : Yes, I do understand that *some* AM3 motherboards do support FX, but the fact that most AM3 boards don't, means FX is not officially supported on AM3. It's strange. It's like AMD got sloppy on the socket. I know this is old news, but the question arises in light of Trinity's launch, and with folks who bought FM1 boards now more than ever feel being left out in the cold.

Basically what Kurotetsu said.

It was a weird situation, because at first AMD said that AM3 would support BD, then they said it wouldn't (amid apeculation that AMD was pressured by the mobo mfr's), then some mobo mfr's released BIOS updates to support BD. From what I understand, the SB870 and higher AM3 sockets are capable of supporting BD with a BIOS update.

And yeah, the FM1 folks are totally screwed. Shame on AMD!

Last edited by Yeats on Tue Oct 09, 2012 4:24 pm, edited 1 time in total.

DPete27 wrote:On a related topic. How does PCIe 3.0 support from AMD fit into all this? Can they add PCIe 3.0 to AM3+ without moving to a new socket? My guess is no.

I think so? I believe PCIe 3.0 got added to Ivy Bridge CPUs and they still used LGA1155. As long as the new PCIe version doesn't require any extra pins, which I don't think 3.0 does, the current socket should be okay (of course, your motherboard needs to support it too).

Why? AMD didn't put a new socket in there just for laughs. AMD knows it'll sell more CPUs if it can maintain socket compatibility, so it only makes new sockets when it has to. There's no shame in doing what's best for the platform. I think expectations by enthusiasts are too demanding concerning this.

How did we get screwed? I put an A8-3850 on an F1A75-M Pro last August. It's still working just fine. I replaced it with a Core i5-3570K on a P8Z77-M Pro in May and handed down the Socket-FM1 package to a family member whose NForce4 ultra socket-939 motherboard had finally given up. When I buy another processor, I'll get another new motherboard, too. No biggee.

This is a late addition to the thread. However, I realized just now (when I was poring over the forums) what other benefit AM3+ offers FX buyers: DDR3-1866 support. Of course it wouldn't hurt if one could run the FX with good old DDR3-1333, but that would probably make the FX look worse than it already does next to Intel.

Just a bit of additional thought.

If people stick with you just because you have a Rolex on your wrist, you can bet losing them is as OK as losing an Invicta. And if they stick with you even if you only have an Invicta, losing them is as OK as losing a Rolex.

It is not up to AMD to make boards compatible, it is up to the board vendors and the coding of the bios and the design of the power circuit. AMD has nothing to do with making a board forward or backward compatible other than the pin count and pin layout.

Cybert said: Capitlization and periods are hard for you, aren't they? I've given over $100 to techforums. I should have you banned for my money.